Sweet pepper plants of the species Capsicum annuum belong to the Nightshade family, also known as Solanaceae. It is an annual herbaceous flowering plant species native to South America.
Pepper plants are being cultivated worldwide for their highly nutritious fruits. In 2012 the acreage for sweet peppers in the United States was approximately 55.5 million, with a production of about 848,160 tons (source USDA). The pepper fruits have a high vitamin A and C content, as well as a high content in dietary fiber. Bell peppers are eaten raw, cooked, immature and mature and may be processed into powders, sauces, and salsas. The fruits in the unripe stage are usually green, but during ripening they usually become red, although other colors are known such as: yellow, orange, purple, white, and brown.
There are various ways of cultivating peppers, the most common are: open field, greenhouse and shade house production. Although the species can be grown under a wide range of climatic conditions, it performs most successfully under dry and warm conditions.
The genus of Tobamoviruses is a group of rod shaped viruses capable of infecting a wide array of species, including Capsicum species. Pepper infecting strains of Tobamovirus are subgrouped into ‘pathotypes’, according to their reactions on a set of differential Capsicum sp. hosts. Pathotype P0 corresponds to Tobacco Mosaic virus (TMV) and/or Tomato Mosaic Virus (ToMV) pathotype, and pathotype P1 corresponds to ToMV as well. Pathotypes P1-2 and P1-2-3 belong to isolates of Pepper Mild Mottle Virus (PMMoV). Symptoms on susceptible plants can vary considerably depending on the strain of virus, time of infection, and growing conditions. Foliar symptoms include mosaic, mottling, leaf distortion and sometimes leaf death and defoliation. Fruits of infected plants may be undersized, deformed, mottled or blotched and have a rough surface. Infected seedlings are usually stunted and pale. Tobamoviruses are easily transmitted through contact and can be transmitted by seed. Especially in greenhouse cultivation Tobamoviruses can be a problem due to the higher plant density compared to open field cultivation. Tobamoviruses are responsible for significant economic losses in pepper production areas. Genetic resistance to Tobamoviruses is thus highly desired.
Mexico is the second largest pepper producing country in the world. A large part of the pepper cultivation in Mexico takes place in the open field or simple low-tech poly tunnels. Pepper varieties in Mexico cope with different environmental influences compared to cultivation in uses in northern regions. For greenhouse conditions in regions at higher latitude it is important to grow pepper plant varieties that have an open growth, a foliage that covers the pepper fruit as little as possible, in order to let as much light as possible through for the maturing of the fruit.
In contrast, in regions/countries at a low latitude, with subtropical or tropical climate, such as Mexico, there is an abundance of light, and often even too much light. The strong direct sunlight can damage the fruit, causing so-called sunburn. Fruit that is damaged by sunburn cannot be sold. Pepper varieties that would have a more closed growth and closed foliage that covers more of the fruit, are preferred in these kind of conditions.
In the cultivation system that is applied in Mexico, two stems at the dichotomy (fork) are kept, instead of pruning one (or pruning two stems in case three branches split off) of the stems as is regularly done in cultivation systems in greenhouses in Europe, US, and Canada. The flower that appears in the centre of the fork is kept instead of pruned. Most pepper varieties however, do not have a balanced dichotomous growth, often one of the two, or three stems growing from the fork is shorter than the other. Pepper plants with a more uniform stem growth at the dichotomy would result in two uniform stems after the dichotomy, resulting in more flowers per plant and therefore a higher yield per plant.
The color of the pepper fruit at maturity is described in the UPOV test guidelines for sweet pepper cultivars. For pepper fruits that have a red color at maturity, the cultivars Fehér, and Lamuyo are mentioned as comparison.
At the moment there is no pepper variety available for open field and low-tech polytunnel cultivation of pepper in Mexico and areas with a similar climate, which combines traits including medium red colored blocky type fruits, more leaf coverage, resistance against Tobamovirus pathotype P0, P1, P(1-2), and more uniformity in stem growth when grown in 2-stem Mexican cultivation system.
Citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention.